The series has some important things to say about race in America, particularly in explaining how society concocted expedient notions about race that have no backing in genetics or biology - what Mark Twain described as a "a fiction of law and custom."

In Dicey's words it meant that 'whenever men act in concert for a common purpose they tend to create a body, which from no fiction of law but from the very nature of things, differs from the individuals of whom it is constituted.'